The transmission is slipping randomly but it's not storin...


The transmission is slipping randomly but it's not storing a code. The AT light will come on and go off Mechanic's Assistant: This is potentially serious. How long has it been going on? The TCM has been replaced and the t...

The transmission is slipping randomly but it's not storing a code. The AT light will come on and go off Mechanic's Assistant: This is potentially serious. How long has it been going on? The TCM has been replaced and the transmission too but its still doing the same thing. Now the dealer says there's nothing wrong with the tcm and the shop who put in the transmission says there's nothing wrong with that and to drive it until the check engine light comes on Mechanic's Assistant: What is the make/model/year of your transmissions? I have a 2010 mazda 3. It got a used transmission put in with roughly 50,000 miles on it Mechanic's Assistant: Are you fixing your Mazda 3 yourself? What have you tried so far? It's been happening since May. I've been taking it to a mechanic. The TCM and transmission have been replaced and so has the battery Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? Could it be a bad TCM the dealer put in? The mechanic also said the wiring harness looks good...

Automotive Expert
Hello, my name is \*\*\*\*\* \*\*\*\*\* to Just Answer! I will be assisting you with your questions today. Give me one moment while I review this.
Automotive Expert
Here’s the sequence of events I follow: Check fluid level and color. Make appropriate repairs. Check shift solenoids with a scan tool in bidirectional mode if applicable. Shift solenoids are inside the transmission and this is the easiest way to check them. Drop pan and inspect for excessive metal shavings inside pan. Check valve body and clutches visually. Hopefully you may not have to go this far, maybe you just were a bit low on fluid. Hi, I’m Ron and I’m here to help you with your problem. I’m very sorry that your having this issue and together, we will get this figured out. I will need your help too because I can’t see, touch, hear or smell anything that’s going on with your vehicle. We may also require some specialized testing tools in order to assist us in diagnosing the problems due to the complexity of today’s vehicles. Please be patient with my replies, I reply back in question order received. If I send you an attachment, I will tell you, BUT, you will NOT get it on a phone; you must be on a tablet or PC. Please let me know when you are satisfied with my answers too so we can close out your question. Thanks a lot for using JA, Ron Please let me know if you need more help. Thanks, Ron

Could the tcm be bad and not throw a code? I had it replaced in May and I had the transmission replaced also but the car is still having the problem but now it's not storing a codeThe mechanic said I should drive the car until the check engine light comes on ��
Automotive Expert
Yes it can. Whatever, I'm just trying to help with these issues you're having and would like to see if the shift solenoids are working right. Thanks again, Ron

Ok thanks. Initially the car had a shift solenoid code but it's not doing that anymore. I don't know how to check them
Automotive Expert
Bidirectionally with a SCAN TOOL. Thanks, Ron

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